01 What is an One-Time Pad?

One-time pad – Wikipedia

The one-time pad is a polyalphabetic monographic substitution method. It uses a key that is at least the same length as the plaintext/chiffertext.

The method was proposed by the cryptologist Frank Miller in 1882 and patented by Gilbert Vernam in 1917.

When used correctly, the method is demonstrably secure and cannot be broken.